Method of monitoring washing water for a developing process of a photosensitive material

Abstract

In a method of monitoring washing water used in a developing process of a photosensitive material, a reference conductivity of the washing water is first calculated in accordance with a equation and based on the conductivity of a processing solution in a bleaching/fixing tank and the conductivity of fresh water for replenishing the washing tank. The conductivity of the washing water in the washing tank is compared with the reference conductivity to determine the degree of contamination of the washing water. Since the conductivity of the processing solution may vary due to evaporation thereof or the like, the reference conductivity is updated at periodic intervals. Accordingly, the degree of contamination can always be determined based on a proper reference conductivity.

What is claimed is: 
     
       1. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material, wherein washing solution stored in a washing tank, which is one of a plurality of processing tanks for processing the photosensitive material, is monitored so as to determine the degree of mixing of the washing solution with at least one processing solution, wherein said processing solution comprises at least one of a bleaching solution and a fixing solution, wherein mixing of the processing solution and washing solution occurs due to processing of the photosensitive material in at least one processing tank prior to processing in said washing tank, said method comprising the steps of: (a) calculating, at at least one interval, a reference value for the washing solution in the washing tank in accordance with an equation based on the conductivity of the processing solution stored in the processing tank and the conductivity of replenishing solution for replenishing the washing tank, and storing the reference value in a memory means to update the reference value;   (b) measuring the conductivity of the washing solution in the washing tank at periodic intervals; and   (c) comparing the measured conductivity of the washing solution and the reference value to determine the degree of mixing of the processing solution in the washing solution in the washing tank.   
     
     
       2. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 1, further comprising the step of predicting, based on variation in the measured conductivity of the washing solution, the time when the conductivity of the washing solution reaches the reference value. 
     
     
       3. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 1, wherein the equation is the following equation: ##EQU2## wherein C is the reference value, Cp is the conductivity of the processing solution, Cw is the conductivity of the replenishing solution, and m is the dilution ratio. 
     
     
       4. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 1, wherein the equation is the following equation:   C=Cp/m+Cw+f(m)     wherein C is the reference value, Cp is the conductivity of the processing solution, Cw is the conductivity of the replenishing solution, m is the dilution ratio, and f(m) is a term for chemical compensation corresponding to variation due to the addition of an additive into the washing solution.   
     
     
       5. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 1, wherein the step (a) further comprises the step of effecting temperature compensation for the conductivity of the processing solution and the conductivity of the replenishing solution before these values are used in the calculation in accordance with the equation, and the step (c) further comprises the step of effecting temperature compensation for the measured conductivity of the washing solution before the measured conductivity is compared with the reference value. 
     
     
       6. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 1, wherein the step (a) comprises the step of compensating the reference value based on the conductivity of purified washing solution when the washing solution in the washing tank is subjected to purification treatment. 
     
     
       7. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 1, further comprising the step (d) of effecting an alarm process when the result of the comparison in the step (c) indicates that the measured conductivity of the washing solution exceeds the reference value. 
     
     
       8. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 7, wherein in said step (c), the amount of variation in conductivity per unit time and at least one of the amount of variation in conductivity per unit area of the processed photosensitive material is calculated from conductivities obtained from measurements of a plurality of prior intervals, and is respectively compared to the reference value. 
     
     
       9. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 1, wherein the washing tank is the final washing tank when a plurality of washing tanks are provided along the direction of processing of the photosensitive material. 
     
     
       10. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material, wherein washing solution stored in a washing tank, which is one of a plurality of processing tanks for processing the photosensitive material, is monitored so as to determine the degree of mixing of the washing solution with at least one processing solution wherein said processing solution comprises at least one of a: bleaching solution and fixing solution wherein mixing of the processing solution and washing solution occurs due to processing of the photosensitive material in at least one processing tank prior to processing in said washing tank, said method comprising the steps of: (a) measuring the conductivity of a fresh processing solution and the conductivity of the washing solution in the washing tank, after filling the processing tank with the fresh processing solution;   (b) calculating a reference value for the washing solution in the washing tank based on the results of the measurement and in accordance with an equation based on the conductivity of the processing solution and the conductivity of replenishing solution for replenishing the washing tank, and storing the reference value in a memory means;   (c) measuring the conductivity of the washing solution in the washing tank at periodic intervals; and   (d) comparing the measured value of the washing solution and the reference value to determine the degree of mixing of the processing solution in the washing solution in the washing tank.   
     
     
       11. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 10, further comprising the step (e) of predicting, based on variation in the measured conductivity of the washing solution, the time when the conductivity of the washing solution reaches the reference value. 
     
     
       12. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 11, wherein in said step (d), at least one of an amount of variation in conductivity per unit time and an amount of variation in conductivity per unit area of the processed photosensitive material is calculated from conductivities obtained from measurements of a plurality of prior intervals and is respectively compared to the reference value. 
     
     
       13. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 10, wherein the equation is the following equation: ##EQU3## wherein C is the reference value, Cp is the conductivity of the processing solution, Cw is the conductivity of the replenishing solution, and m is a dilution ratio. 
     
     
       14. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 10, wherein the equation is the following equation:   C=Cp/m+Cw+f(m)     wherein C is the reference value, Cp is the conductivity of the processing solution, Cw is the conductivity of the replenishing solution, m is a dilution ratio, and f(m) is a term for chemical compensation corresponding to variation due to the addition of an additive into the washing solution.   
     
     
       15. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 10, further comprising the step of effecting temperature compensation for the conductivity of the fresh processing solution and the conductivity of the washing solution in the washing tank, which are measured in the step (a), before these values are used in the calculation in accordance with the equation in the step (b), and the step of effecting temperature compensation for the measured conductivity of the washing solution, which is measured in the step (c), before the measured conductivity is compared with the reference value in the step (d). 
     
     
       16. A method of monitoring washing solution used in a developing process of a silver halide photosensitive material according to claim 10, wherein the step (b) further comprises the step of compensating the reference value based on the conductivity of purified washing solution, before the reference value is stored, when the washing solution in the washing tank is subjected to purification treatment. 
     
     
       17. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 16, further comprising the step (e) of effecting an alarm process when the result of the comparison in the step (d) indicates that the measured conductivity of the washing solution exceeds the reference value. 
     
     
       18. A method of monitoring washing solution used in a developing process of a color silver halide photosensitive material according to claim 10, wherein the washing tank is the final washing tank when a plurality of washing tanks are provided along the direction of processing of the photosensitive material. 
     
     
       19. A method of monitoring washing solution used in a developing process of a silver halide photosensitive material, wherein washing solution stored in a washing tank, which is one of a plurality of processing tanks for processing the photosensitive material, is monitored so as to determine the degree of mixing of the washing solution with at least one processing solution, wherein mixing of the processing solution and washing solution occurs due to processing of the photosensitive material in at least one processing tank prior to processing in said washing tank, said method comprising the steps of: (a) calculating, at at least one interval, a reference value for the washing solution in the washing tank in accordance with an equation based on the conductivity of the processing solution stored in the processing tank and the conductivity of replenishing solution for replenishing the washing tank, and storing the reference value in a memory means to update the reference value;   (b) measuring the conductivity of the washing solution in the washing tank at periodic intervals; and   (c) comparing the measured conductivity of the washing solution and the reference value to determine the degree of mixing of the processing solution in the washing solution in the washing tank.   
     
     
       20. A method of monitoring washing solution used in a developing process of a silver halide photosensitive material according to claim 19, further comprising the step of predicting, based on variation in the measured conductivity of the washing solution, the time when the conductivity of the washing solution reaches the reference value. 
     
     
       21. A method of monitoring washing solution used in a developing process of a silver halide photosensitive material according to claim 19, wherein the equation is the following equation:   C=Cp/m+Cw+f(m),     wherein C is the reference value, Cp is the conductivity of the processing solution, Cw is the conductivity of the replenishing solution, m is a dilution ratio, and f(m) is a term for chemical compensation corresponding to variation due to the addition of an additive into the washing solution.   
     
     
       22. A method of monitoring washing solution used in a developing process of a silver halide photosensitive material according to claim 19, wherein the step (a) further comprises the step of effecting temperature compensation for the conductivity of the processing solution and the conductivity of the replenishing solution before these values are used in the calculation in accordance with the equation, and the step (c) further comprises the step of effecting temperature compensation for the measured conductivity of the washing solution before the measured conductivity is compared with the reference value. 
     
     
       23. A method of monitoring washing solution used in a developing process of a silver halide photosensitive material, wherein washing solution stored in a washing tank, which is one of a plurality of processing tanks for processing the photosensitive material, is monitored so as to determine the degree of mixing of the washing solution with at least one processing solution, wherein mixing of the processing solution and washing solution occurs due to processing of the photosensitive material in at least one processing tank prior to processing in said washing tank, said method comprising the steps of: (a) measuring the conductivity of fresh processing solution and the conductivity of the washing solution in the washing tank, after filling the processing tank with the fresh processing solution;   (b) calculating a reference value for the washing solution in the washing tank based on the results of the measurement and in accordance with an equation based on the conductivity of the processing solution and the conductivity of replenishing solution for replenishing the washing tank, and storing the reference value in a memory means;   (c) measuring the conductivity of the washing solution in the washing tank at periodic intervals; and   (d) comparing the measured conductivity of the washing solution and the reference value to determine the degree of mixing of the processing solution in the washing solution in the washing tank.   
     
     
       24. A method of monitoring washing solution used in a developing process of a silver halide photosensitive material according to claim 23, further comprising the step (e) of predicting, based on variation in the measured conductivity of the washing solution, the time when the conductivity of the washing solution reaches the reference value. 
     
     
       25. A method of monitoring washing solution used in a developing process of a silver halide photosensitive material according to claim 23, wherein the equation is the following equation:   C=Cp/m+Cw+f(m),     wherein C is the reference value, Cp is the conductivity of the processing solution, Cw is the conductivity of the replenishing solution, m is a dilution ratio, and f(m) is a term for chemical compensation corresponding to variation due to the addition of an additive into the washing solution.   
     
     
       26. A method of monitoring washing solution used in a developing process of a silver halide photosensitive material according to claim 23, further comprising the step of effecting temperature compensation for the conductivity of the fresh processing solution and the conductivity of the washing solution in the washing tank, which are measured in the step (a), before these values are used in the calculation in accordance with the equation in the step (b), and the step of effecting temperature compensation for the measured conductivity of the washing solution, which is measured in the step (c), before the measured conductivity is compared with the reference value in the step (d). 
     
     
       27. A method of monitoring washing solution, using a computer, wherein said solution is used in a developing process of a silver halide photosensitive material, wherein washing solution stored in a washing tank, which is one of a plurality of processing tanks for processing the photosensitive material, is monitored so as to determine the degree of mixing of the washing solution with at least one processing solution, wherein mixing of the processing solution and washing solution occurs due to processing of the photosensitive material in at least one processing tank prior to processing in said washing tank, said method comprising the steps of: (a) calculating, at at least one interval, a reference value from signals corresponding to the conductivity of the processing solution and the conductivity of a replenishing solution for said washing solution, in accordance with an equation;   (b) measuring the conductivity of the washing solution at periodic intervals; and   (c) comparing the measured conductivity and the reference value to determine the degree of mixing of the processing solution in the washing solution.   
     
     
       28. The method of monitoring washing solution according to claim 27, wherein said equation is the following: ##EQU4## wherein C is the reference value, Cp is the conductivity of the processing solution, Cw is the conductivity of the replenishing solution, and m is the dilution ratio. 
     
     
       29. A method of monitoring washing solution, using a computer, wherein said washing solution is used in a developing process of a silver halide photosensitive material, wherein washing solution stored in a washing tank, which is one of a plurality of processing tanks for processing the photosensitive material, is monitored so as to determine the degree of mixing of the washing solution with at least one processing solution, wherein mixing of the processing solution and washing solution occurs due to processing of the photosensitive material in at least one processing tank prior to processing in said washing tank, said method comprising the steps of: (a) measuring the conductivity of fresh processing solution and the conductivity of the washing solution after filling the processing tank with the fresh processing solution;   (b) calculating a reference value from signals corresponding to the measured conductivity of the processing solution and the measured conductivity of a replenishing solution for said washing solution, in accordance with an equation;   (c) measuring the conductivity of the washing solution at periodic intervals; and   (d) comparing the measured conductivity and the reference value to determine the degree of mixing of the processing solution in the washing solution in the washing tank.   
     
     
       30. The method of monitoring washing solution according to claim 29, wherein said equation is the following: ##EQU5## wherein C is the reference value, Cp is the conductivity of the processing solution, Cw is the conductivity of the replenishing solution, and m is the dilution ratio.